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Subject: Re: [OMPI users] strange IMB runs
From: Michael Di Domenico (mdidomenico4_at_[hidden])
Date: 2009-08-14 10:57:03


On Thu, Aug 13, 2009 at 1:51 AM, Eugene Loh<Eugene.Loh_at_[hidden]> wrote:
> Also, I'm puzzled why you should see better results by changing
> btl_sm_eager_limit. That shouldn't change long-message bandwidth, but only
> the message size at which one transitions from short to long messages. If
> anything, tweaking btl_sm_max_send_size would be the variable to try.

Changing this value does tweak the 1,2,4MB messages, but all others
are the same and it's not consistent.

I've also noticed that the latency is nearly 2usec high on OpenMPI vs HPMPI